Processing and levitation force in top-seeded YBCO

Author

Yu, R. ; Mora, J. ; Pinol, S. ; Sandiumenge, F. ; Vilalta, N. ; Gomis, V. ; Martinez, B. ; Rodriguez, E. ; Amoros, J. ; Carrera X Granados, M. ; Camacho, D. ; Fontcuberta, J. ; Obradors, X.

Author_Institution

Inst. de Ciencia de Mater., CSIC, Barcelona, Spain

Volume

7

Issue

2

fYear

1997

fDate

6/1/1997 12:00:00 AM

Firstpage

1809

Lastpage

1812

Abstract

Bulk cylinders of YBa/sub 2/Cu/sub 3/O/sub 7/-Y/sub 2/BaCuO/sub 5/ composites, up to 35.0 mm in diameter, have been melt-processed using MgO single crystals, Nd123 and Sm123 melt textured ceramics, as seeds. The influence of processing parameters has been examined in order to optimize the growth conditions. Polarized light microscopy, SEM and EDX, have been used to characterize the orientation, size and morphology of the grains, as well as the spatial distribution and size of Y211 particles. An increase of the levitation forces is observed when the top seeding growth is carried out under a temperature gradient. The trapped magnetic and the levitation force of a single domain sample was systematically measured and theoretically simulated by finite element calculations. The deduced J/sub c/ from the different experiments have been compared and analyzed.

Keywords

X-ray chemical analysis; barium compounds; crystal growth from melt; crystal microstructure; crystal morphology; crystal orientation; grain size; high-temperature superconductors; magnetic levitation; optical microscopy; scanning electron microscopy; yttrium compounds; EDX; SEM; YBa/sub 2/Cu/sub 3/O/sub 7/-Y/sub 2/BaCuO/sub 5/; YBa/sub 2/Cu/sub 3/O/sub 7/-Y/sub 2/BaCuO/sub 5/ composites; grain morphology; grain orientation; grain size; growth conditions; high temperature superconductor; levitation force; melt textured ceramics; melt-processed; polarized light microscopy; processing parameters; spatial distribution; top-seeded YBCO; Ceramics; Crystals; Force measurement; Levitation; Morphology; Numerical analysis; Optical polarization; Scanning electron microscopy; Temperature; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.620934

Filename

620934